What is a waterway? Can that term encompass paths across the landscape that are only occasionally wet? For decades federal courts and presidential administrations have decided yes and then no and then yes again.  No one, not the courts or federal agencies like the U.S. Environmental Protection Agency or the Army Corps of Engineers, can seem to resolve the question for good. In 2006, the late Justice Antonin Scalia, writing the court’s decision to limit the definition of a waterway, famously mocked the idea of water in the desert, detailing all the instances of lower courts upholding seemingly ludicrous water bodies.